The Three dimensions of NGSS are science practices, crosscutting concepts and disciplinary core ideas. The science practices allow students to gather skills scientists use. Students learn how to engage and perform scientific tasks such as experiments. The cross-cutting concepts is where students use things such as patterns, cause and affect etc. these are found across all science topics. The core ideas sections break the sciences down into sections. In these you find life science, earth science, stem etc. By connecting all of these ideas students can become experts in scientific topics. When all three areas are addressed and taught together stduents can relate informational and from background knowledge about topics and understanding. NGSS was created to help improve students within science across the states, by using NGSS students science skills are shown to improve. 

Resource Link Home Page | Next Generation Science Standards